MIGRATIONS OF WATERFOWL 



Some overland journeys of these mass migrations carry the birds far, 

 sometimes hundreds of miles, over terrain where we cannot read the pattern 

 of their flight in the scheme of water areas. Several wildfowlers of Sas- 

 katchewan and Montana have told me of a late autumn mass movement of 

 ducks that moves due south across central Saskatchewan and eastern Mon- 

 tana. Mr. Harry Jensen, of the U.S. Fish and Wildlife Service, told me of a 

 mass flight he watched pass over eastern North Dakota in the autumn of 1944. 

 The passage, moving south, lasted one and one-half hours and the birds 

 were so high that most of them could not be seen without the aid of bin- 

 oculars. 



Waterfowl favor rivers leading from one part of the range to another, but 

 do not use those crossing this main line of travel. Ducks departing south- 

 east from Delta have an overland flight of about twenty miles to the Assini- 

 boine River, which they might follow to the Red River by turning east. 

 Instead they cross the east-west line of the Assiniboine and continue, to 

 meet the Red River Valley near the Minnesota border. 



The volume of the mass passages is tremendous beyond belief. Rowan 

 (1929b) describes a November exodus from Alberta when, as one farmer ex- 

 claimed, the migrants were so numerous that "the sky was black with them, 

 flying in formation like geese, in bunches of around thirty to forty. As to 

 numbers, all I can say is that they passed over in thousands." At the peak of 

 a three-day migration Sowls (1947a) estimated that at least 100,000 ducks, 

 mostly Lesser Scaup, flew over the Delta Marsh during one hour on Novem- 

 ber 6, 1947. 



These big "pushes" are seldom confined to one marsh region; there is 

 often a movement of waterfowl over a range that is wide and deep. In 1950 

 the big freeze-up migration at Delta was on November 8 and 9. Colonel 

 Arthur Sullivan reported major flights over the south end of Lake Winnipeg 

 the same days. At Whitewater Lake, Bossenmaier saw the heaviest flight on 

 the eighth, while at the same time, Merrill Hammond watched the last of 

 the waterfowl leave the Lower Souris Refuge in North Dakota. At Aberdeen, 

 South Dakota, Jerry Stoudt observed a major flight of waterfowl going to 

 the southeast on the eighth, and Warren Nord saw a massive migration of 

 Mallards and diving ducks near Fergus Falls, Minnesota, that same after- 

 noon. D. H. Janzen,* traveling in North Dakota, found that the big move- 

 ment out of that state commenced on November 7 and continued through 



The accounts by Janzen, Hammond, Stoudt, Bossenmaier, and Lynch are from manuscript 

 reports supplied by the U.S. Fish and Wildlife Service. 



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